Use this mortar calculator to estimate premixed mortar bags from brick or block counts, or a coverage rate supplied for your product.
Use the coverage for your actual mortar product
Divide the quantity of work by the coverage stated for the actual mortar product. For bricks or blocks, use the number being laid. For wall-area coverage, use the net wall face after openings and match its area unit to the supplier rate. The tool converts square feet and square meters when those units differ. The QUIKRETE Mortar Mix 1102 data sheet gives an upper coverage estimate for its 80 bag: 37 standard bricks or 13 standard 8 × 8 × 16 blocks. These are product-specific coverage bases, not a guarantee for every joint or placement method. Check the project conditions and product instructions before relying on that upper coverage figure.
For another product or bag size, choose supplier units per bag or supplier wall area per bag. Enter its documented rate; changing bag mass alone does not establish coverage.
Exclude unused spare bricks and stock left over from whole supplier packs. Count the standard masonry units actually used; individual cut-piece layouts and joint geometry require a project-specific coverage check.
Extra mortar is an entered project allowance, with a default of 0%. Optional price multiplies the final whole-bag quantity in your entered currency; no market price is assumed.
Mortar Calculator example
- For 37 standard bricks, select the QUIKRETE 1102 brick basis and leave extra mortar at 0%.
- At the published maximum coverage, the engine gives 1 bag before rounding and 1 bag to buy.
- Check the actual joint and placement conditions before treating maximum coverage as a purchasing plan.
Separate bag rounding from an entered allowance
Apply the entered allowance to the unrounded bag equivalent, then round upward once. Do not round the base bag count first and apply extra to that already rounded count.
The 130-block preset returns 10 bags at the published maximum and no entered extra. In the custom wall-area preset, 200 divided by an entered 25 per bag gives a base equivalent of 8 bags. An entered 10% allowance produces 8.8 bags before rounding, so the result is 9 bags. The 25 per bag rate is arbitrary arithmetic, not measured or recommended coverage for any product. For standard brick or block work, use the matching count basis unless your actual supplier publishes an applicable wall-area rate.
Whole-bag rounding matters most near a boundary: the 37-brick example with an entered 10% allowance becomes 1.1 bags before rounding and 2 bags to buy. The allowance is a choice for the project, not a universal waste rule.
The two published unit-count bases come from the manufacturer’s data sheet.
When an unrounded estimate is close enough to a whole bag that its display would hide the difference, the tool labels it “just over” or “just under.” A value just above a whole bag still needs the next bag. Very long decimal entries that cannot be preserved are rejected instead of silently changing the buying threshold.
Keep laying mortar separate from block-core fill
This tool estimates premixed mortar used in laying masonry joints. It does not calculate thinset for tile, dry cement-and-sand recipes, material to fill hollow block cores, or the mortar strength/type required by a design. A product-specific laying rate cannot answer those separate questions.
Brick Calculator estimates wall bricks and supplier packs; its purchased total can include spares that are not laid. Concrete Block Calculator handles concrete masonry unit counts and optional entered core-fill volume separately. For an irregular face, use Square Footage Calculator to measure nonoverlapping areas before entering a wall-coverage rate. A poured footing belongs in Concrete Calculator.